Anesthesia for cardiac surgery.pptx

ANAESTHETIC MANAGEMENT OF CARDIAC SURGERY Dr.Abdullah Al.Ashwal  Anaesthetic Management Of Cardiac Surgery Anaesthesia for Cardiac Surgery, with a few Important Exceptions such as Emergencies, most Cardiac Anaesthesiologists apply a Standardized An...

ANAESTHETIC MANAGEMENT OF CARDIAC SURGERY Dr.Abdullah Al.Ashwal  Anaesthetic Management Of Cardiac Surgery Anaesthesia for Cardiac Surgery, with a few Important Exceptions such as Emergencies, most Cardiac Anaesthesiologists apply a Standardized Anaesthetic Technique to all But a few of their Patients. in Which They Will Adapt There Plan to the Pathology That They Will Have.  Anaesthetic Management Of Cardiac Surgery Objectives:  Preoperative Preparation  Intraoperative Management  Postoperative Management  Preoperative Preparation * History. Medical History. Surgical History. Drug History. Previous Anaesthesia * Examination. Cardiovascular. Respiratory. Spine And Vertebra. Air Way Assessment  Preoprative Preparation * Investigations. Value Of Test. Risk And Cost Benefit. Preoperative Testing: Base On Indication  Laboratory Data  CBC :. Hb 7g/Dl In Healthy Patient. Hb 10 G/Dl In Cad. Red Blood Cell Morphology,plt. Count  Blood Chemistry:. Glucose. Bun/Cr. Coagulogram. Liver Function Test  CXR  Urinalysis, Pregnancy Test  ECG  Laboratory Data Specific Tests: * Cardiac Evaluation: - Exercise Stress Test - Thallium Scan - Echocardiogram *Pulmonary Evaluation: - Lung Function Test - Spirometry - Arterial Blood Gass * Vascular Evaluation: - Lower Limb Doppler - Carotid Doppler  Preoprative Preparation  Consent Form: Informed Consent Involves: - Discussing Anesthetic Management Plan, Alternatives. - Potential Complication.  NPO Guideline * Adult: - NPO 6-8 Hrs Before Surgery - Clear Liquid Diet For 2 Hr. *Children: - Clear Liquid 2 Hr - Breast Milk 4 Hr - Infant Formula 6 Hr - Solid Diet 8 Hr.  Guideline Used For Patient With No Problem With Gastric Emptying Time  Premedication  Objectives * Anxiolytic And Sedation * Analgesia * Amnesia * Hemodynamic Stability * Decrease Secretion * Decrease Gastric Volume * Antiemetic * Facilitate Induction Of Anesthesia * Antiinfection  Premedication  Medications:  Psychological - Benzodiazepin Support: - Butyrophenone - Describe Anesthetic - Opioids Technique Available And - Aspiration Prevention - Antiemetic Risk. - Heamodynamic Stability - Describe What To Expect In. Alpha 2 Agonist (Clonidin) Or.. B Blockers (Atinelol) - Antibiotics - Describe Duration And Time Premedication  Preparation For Induction Of Anaesthesia  Pre-arrival Preparation. - Before the arrival of the patient in the anaesthesia or operating room, most especially in Emergencies, The Operating Room and Staff should be Present and Prepared. - All the Anaesthetic Drugs should be Drawn-up in syringes, as well as Heparin, an Antibiotic, and any Cardiovascular Drugs that might be required.  Preparation For Induction Of Anaesthesia  Pacemakers And Automatic Implantable Cardioverter/Defibrillators If the patient has a permanent pacemaker that has not already programmed to a non-sensing mode set at a suitable high rate such as 80 beats per minute, then this may be done before induction of anaesthesia and certainly before the start of surgery as diathermy may inhibit discharge of the pacemaker.  Intraoperative Management  Objectives:  Positioning  Monitoring  Induction Intraoperative Management - Positioning  Intraoperative Management - Monitoring  Standard Monitoring:  A Qualified Anesthesiologist ( Standard I ). Presence of an Anesthesiologist Is The Most Important Monitor.  Essential Monitoring for all Anesthetized and ICU cases includes Basic Monitoring ( Standard II ). - ECG - Non-invasive BP - Pulse Oximetry - End-tidal CO2 - Neuromuscular Monitoring. - Body Temperature. - Gas Analysis.  Intraoperative Management - Monitoring  Basic monitoring:  ECG ≥2 leads (II and V5) Baseline print of all leads ST-segment analysis  Pulse Oxymetry  Backup Manual or Automatic Blood Pressure Cuff  Intraoperative Management - Monitoring  Venous Access: Two large-bore (16-gauge or larger) peripheral IV catheters One central venous line, usually IJV Measurement of central venous pressure PA-catheters: on indication as: - Low EF - pulm. Hypertension - complex procedures.  Arterial cannulation: Insert Before Induction Of Anesthesia Non-dominant Hand (Caveat: Radial Art. Harvesting) Direct And Continuous Measurement Of Arterial Blood Pressure  Intraoperative Management - Monitoring  Others:  Indwelling Urinary Catheter Urine output, bladder temperature  Temperature Probes Esophageal, nasopharyngeal, skin, bladder, tympanic, blood  Cross-matched Blood Available Especially if patient has already had a midline sternotomy  Consider Thoracic Epidural Anesthesia (Only Europe)  Intraoperative Management -Induction  Goal: Hemodynamic Stability  Selection Of Induction Agents: High-dose Opiates ± Benzodiazepine Modest dose of IV Anaesthetic Agents Muscle Relaxant, Endotracheal Intubation Vasopressor If Blood Pressure Falls >20%  Maintenance Of Anesthesia  Selection Of Anesthetic Technique/Agents: TIVA with short acting agents, covers whole procedure Volatile Anesthetic Agents - Cardioprotection - Difficult to use during CPB  Avoid N2O! (expansion of intravascular air bubbles, pneumothorax)  High-dose opiates  Muscle relaxants  Vasopressor if blood pressure falls >20%  Goal: Early Extubation (1–6 H Postop.),Fast Track  Maintenance Of Anesthesia  Sternotomy  Anticoagulation: Must Be Established Prior To CPB. Must Be Confirmed With Determination Of The ACT. Heparin: 3-4 Mg/Kg (Opcabg: 2 Mg/Kg).  Cardiopulmonary Bypass  CPB diverts venous blood away from the heart, adds oxygen, removes CO2, and returns the blood to a large artery. As a result, most blood flow through the heart and most of the flow through the lungs cease. Flow = Non-pulsatile  Organ Protection: Hypothermia Cardioplegia (cold, K+-rich, blood or crystalloids, ante- and  Cardiopulmonary Bypass  Going on-pump  Confirm Adequate Anticoagulation (ACT) Before Cannulation  Venous Cannulation  Aortic Cannulation Reduce Systemic Arterial Pressure (to 90–100 mm Hg systolic) Complications: Aortic Dissection, Cerebral Embolism (Plaque, Air)  Cardiopulmonary Bypass  Initiation of CPB Is Associated with:  A marked increase in stress hormones  A Variable Systemic Inflammatory Response (Sepsis- like) * Generation of oxygen-derived free radicals  Activation of multiple humoral systems, including Complement, Coagulation, Fibrinolysis, and the Kallikrein System  Mechanical Trauma Alters Platelets And Activates Leukocytes  Cardiopulmonary Bypass  Start CPB, Pump Flow Gradually Increased to 2–2.5 L/min/m2  Reduce Temperature  Cross-clamp  Cardioplegia  Maintain MAP 50 - 80 mmHg (Organ Perfusion)  Hemodilution due to CPB priming  Keep Hematocrit between 20% and 25%  Cardiopulmonary Bypass  Intraoperative Laboratory Monitoring:  Blood Gas Analysis (Point of Care): Hematocrit Serum Potassium Ionized Calcium Glucose  Activated Clotting Time (ACT) Reference value ranges between 70-180 sec During CPB the desired range is >400-500 sec During OPCAB procedures usually >300-400 sec  Cardiopulmonary Bypass  Weaning From CPB (Preparation):  A "Hot Shot" or warm blood cardioplegia can be administered * To wash out byproducts * Replenish Metabolic Substrates  Optimise physiological conditions * Acidosis and hypoxia should be corrected * Lung ventilation must be resumed * Normothermia (≥36°C) should be achieved * Normovolemia should be achieved *Hb should be kept ≥5 mmol/L  Cardiopulmonary Bypass  Surgeon unclamps the Aorta * Washes out cardioplegia (Heart Re-starts)  Re-start Pulmonary Ventilation  Continue CPB 1/3 to ½ cross-clamp time after heart re-start * Keep heart in empty and beating state * Stabilizes heart, minimal metabolic requirements  A Stable Rhythm (Preferably Sinus) must be present  * Atrioventricular pacing may be necessary (80–100 bpm)  TEE Monitoring (Chamber Vols, Contractility,  Weaning Problems: 1- Poor Cardiac Function Consider inotropic support: * dobutamine (1st choice) * milrinone (esp. right ventricular failure) * Norepinephrine * (epinephrine, dopamine) * Levosimendan (not approved in NL) Consider reperfusion Consider afterload reduction (nitroprusside, milrinone) Consider intraaortic balloon pump (IABP)  Weaning Problems: 2- Residual Air Problem : (TEE, ECG) Solution: * Evacuate air from the heart and any bypass grafts * increase perfusion pressure (norepinephrine) 3- Hypoxia : Hypoxia on weaning from CPB is uncommon, but important to detect, as it can precipitate cardiovascular collapse as it causes myocardial dysfunction. Causes: Inadequate re-expansion of the lungs Pulmonary oedema Shunting through a septal defect  Reversal Of Anticoagulation:  Protamine binds and effectively inactivates heparin  Dose: 1 mg of protamine per mg of (initial) heparin  Infuse slowly  Hemodynamic side-effects * Hypotension (vasodilation) * myocardial depression * pulmonary hypertension * Allergic reactions  Check effect with ACT  Consider supplemental protamine (50–100 mg) after administration of CPB blood  Off Pumb Stage  Securing Haemostasis - After successfully weaning from CPB, the surgeon has to decannulate and, importantly, secure haemostasis.  Chest Closure - Once haemostasis has been secured, sternal closure is next important surgical event for the anaesthetist, as it may precipitate hypotension  Transfer To Critical Care Unit  Transferring patient from the Operating Room to the ICU or Recovery Areas is also a Vulnerable Period when there may little immediate Technical or Human support.  Direct measurement of SAP and ECG are the Minimum required for Monitoring.  Pulse Oximetry is also valuable to detect Hypoxia.  Drugs for Resuscitation should be taken with the  Postoperative Management  On arrival in the critical care area, monitoring needs to be transferred and the Patient Established on the Mechanical Ventilator.  IV infusions and drug infusion pumps should be transferred and connected to the mains electrical supply.  Once the physical transfer is complete and the patient condition is stable, a full Verbal and Written Handover to Medical and Nursing Staff should be undertaken before the anaesthetist leaves the patient. THANK YOU